NV5 prepared a Sampling and Analysis Plan (SAP), Quality Assurance Project Plan (QAPP), Health and Safety Plan (HSP), and Integrated Site Assessment (ISA) Report for this mine site, pursuant to CERCLA guidelines. The site is located in the Humboldt-Toiyabe National Forest approximately 10 miles northeast of Bridgeport, California.
Field x-ray flourescence (XRF) analysis was performed to delineate the lateral and vertical extent of approximately 30,000 cubic yards of mill tailings, which contained arsenic, mercury, and other heavy metals, in a five-acre drainage area within Masonic Gulch.
Laboratory analysis of soil, sediment, and surface water samples was performed to characterize the nature of the tailings. Biological inventory was performed to identify potential receptors and to facilitate the development of a conceptual model for the site.